Robot operating system (ROS) is an open source meta-operating system, which can provide a structured communication layer based on message mechanism on heterogeneous computing clusters. In order to improve the real-time and reliability problems of data distribution in ROS1, ROS2 is proposed with data flow oriented data distribution service mechanism. This study adopts the method of probability model test and analysis, validates real-time and reliability of the ROS2 system. Firstly, a data flow oriented ROS2 data distribution service system of communication formal validation framework is put forward, and the communication system module probabilistic timed automata model is set up. Secondly, probabilistic model detector PRISM is used to verify the real-time and reliability of ROS2 data flow oriented data distribution service through parameter analysis of data loss rate and system response time. Finally, based on retransmission mechanism, quality of service (QoS) strategy analysis, through the set up and adjust service quality parameters, different data requirements and quantitative performance analysis of transmission mode are achieved, providing the reference for application designers based on ROS2 and distributed data distribution service based on the data flow of formal modeling, validation, and quantitative performance analysis.